Reinforcing material



' .Feb. 15, 1944. M, I W 2,341,713

REINFORCING MATERIAL Filed July 28. 1941 Patented Feb. 15, 1944 REINFORCING MATERIAL Stanley M. Griswold, Newton, Mass., a'ssignor to ,B. B. Chemical.Co., Boston, Mass., a corporation of Massachusetts Application July 28, 1941, Serial No. 404,299

6 Claims.

This invention relates .to reinforcing material comprising woven fabric, and more particularly to tape suitable for use in reinforcing insoles.

This application is a continuation of my ap- I plication Serial No.-30 5,526, filed November 21,-

1939. Insoles embodying the reinforcing material of this invention and methods of reinforcing insoles therewith are disclosed and claimed in my copending application Serial No. 291,939, filed August 25, 1939, now Patent No. 2,255,353.

Objects of this invention are to provide reinforcing material of improved characteristics, and to provide reinforcing material suitable for use in reinforcing insoles of the type disclosed in my above-mentioned copending application Serial No. 291,939.

In accordance with the above and other objects, I have provided reinforcing material comprising woven fabric which has a coating of stiffening material on one side thereof which extends into the substance of the fabric and stops short of the opposite side. of the fabric, and which does not affect substantially the fibrous nature or characteristics of the surface of the fabric. reinforcing material has-a coating of adhesive on the same side of the fabric as the stiffening ma-' terial, which adhesive coating is anchored to the fibrous structure of the fabric.

The reinforcing materialis preferably in the form of a tape prepared from a strip of woven fabric. The fabric may be of any suitable kind, but preferably is that known as duck, and for the purpose of reinforcing insoles I prefer to use duck, the transverse threads of which are sufficiently strong so that a one-inch length of strip has a tensile strength'transversely thereof of not less than about '75 pounds, and preferably such tensile strength should be in the neighborhood of 100 pounds or more.

The stiffening material is preferably of a thermoplastic nature, and may consistof or include such materials as shellac, gum dammar, gum copal, cumarone resin, or Nuba pitch. Because ployed, derived either from a colloidal solution of rubber in an organic solvent, or from latex. The

. latter is preferred. The invention also contemplates the use of synthetic rubber-like materials, such as neoprene.

The adhesive is anchored to the fibrous structure of the reinforcing fabric and extends into the substance of the fabric on .the same side thereof as said thermoplastic stiffening material, but stops short of the opposite side of the fabric.

By the ,present invention there is provided a reinforcing material which is suitably stiffened, wherein the adhesive material andthe stiffening material are applied to the same side of the fabric and, yet, wherein the adhesive material is anchored directly to the fibrous structure of the fabric.

By reason of the application of the adhesive and stiffening materials to the same side of the fabric, the other side of the fabric may be left in its original state and free from coating substances. This feature is advantageous in reinforcing tapes for insoles, for in such cases no additional resistance is offered to the movement of shoe machine parts in shoemaking operations, for example, the channel guide of a welting machine, or the anvil of a staple lasting machine.

Furthermore, the absence of adhesive and stiffening material from one side of the reinforcing material makes possible the winding of the fabric into rolls without adhesion between adjacent layers.

The use of stiffening material of a thermoplas- I tic nature makes it possible, by the application of its inexpensiveness and. generally desirable,

characteristics, I prefer the use of Nuba pitch,

which is a thermoplastic coaltar pitch manufactured by the NevilleCompany, Pittsburgh, Pennsylvania, The Nuba pitch as commercially supplied comes in grades having various melting The adhesive which is applied to the reinforc ing material is preferably pressure-responsive,

-. and of a rubber-like nature. Rubber may be emthe inner face of the lip or rib of which and a portion of the body whereof have been reinforced by the useof reinforcing material of this invention and in accordance with the method of my copending application Serial No. 291,939, referred to hereinabove;

Fig. 2 isa photomicrographjakenat eighteen diameters magnification of'the surface of a piece of duck employed in preparing the reinforcing fabric of the'invention, taken prior'to the application of stiffening or adhesive material and showing the fibrous nature of the surface;

Fig. 3 is a photomicrograph (18 diameters magniflcation) similar to Fig. 2 showing the fabric after the application of Nuba pitch stiflenlng material thereto and illustrating the retention of fibrous characteristics by the fabric;

Fig. 4 is a photomicrograph (18 diameters ma nifi'cation) similar to Fig. 3 showing the fabric after the application of latex adhesive coating to the Nuba pitch-coated surface of the fabric;

able solution employing Nuba pitch is as follows Per cent by weight 70 Nuba pi h Benzene 15 Naphtha 15 If desired, the stiffening material may be applied to'the fabric in the form of an emulsion. Thus, a solution of Nuba pitch in organic solvents may be associated with water with the aid of an emulsifying agent to form an emulsion.

For the adhesive coating, the adhesive material, for example rubber, may be in the form-of a solution in an organic solvent or in the form of an aqueous dispersion. Latex, a natural dispersion of rubber in water, is preferred. The latex may contain, for example,'50% of rubber.

In a specific illustration of the invention, there is provided a fabric such as duck 2 having the warp threads 4 and the woof .or filler threads 6. The filler threads 6 whichlater form the transverse threads of the tape 8 are sufliciently strong so that a one-inch length of strip 8 has a tensile strength transversely of the strip and longitudinally of the woof threads 6 of not less than about '75 pounds and preferably in the neighborhood of 100 pounds or more.- The flbrous structure of the surface of the fabric 2 prior to coating maybe seen in Fig. 2.

The stiffening material, for example the Nuba 'pitch coating, may be applied in a spreading machine of the usual type. Thus, the Nuba pitch emulsion such as described hereinabove may be applied to a fabric in a spreading machine with the doctor blade so adjusted as to remove excess material from the surface of the fabric.

The consistency or viscosity of the stifiening composition and the speed of movement of the fabric through the spreader is such' that the Nuba pitch l0 extends into the substance of the fabric but stops short of the opposite side [2 of the fabric (Fig. 5). Furthermore the stiffening into a bath of latex with the Nuba pitch-coated surface of the fabric in contact with the rolls. As previously pointed out, the latex should not penetrate through the fabric to the side thereof opposite from the Nuba pitch. On the other hand, according to circumstances, the adhesive coating on the same side of the fabric as the stiffening material may be made of any thickness desired. In Figs. 4 and 6 the rubber coating ll deposited from the latex may be seen on the same sidecf the fabric as the Nuba pitch coating III,

NashPatent 2,242,248, granted May 20, 1941. For application to an insole 18, the strip 8 con-' veniently may be prepared in widths of from onehalf to one inch.

The insole [6, which is described and claimed in my copending application Serial No. 291,939, is provided with the upturned lips or ribs l8 and the fabric strips 8 are adhesively secured to the adhesive coated area 20 which includes the inner face of the lip or rib l8 and a portion of the body of the insole I6. The adhesive on the area 28 is preferably of the same nature as the adhesive previously applied to the strip.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. Reinforcing material comprising woven fabric, a coating of stiffening material on one side of said fabric extending into the substance thereof, stopping short of the opposite side thereof and not affecting substantially the ii"- brous characteristics of the surface of the fabric,

.and a coating of adhesive on the same side of the fabric as said stiffening material, said adhesive coating being anchored to the fibrous structure of the fabric.

2. A reinforcing tape comprising a strip of duck, the transverse threads of which are suf- .material l0 does not affect substantially the fificiently strong so that a one-inch length of strip has a tensile strength transversely thereof of not less than about 75 pounds, said strip being provided on one surface with a coating of stiffening material extending into the substance thereof, stopping short of the opposite side thereof and not affecting substantially the fibrous characteristics of the surface of the duck, and a coating of adhesive on the same side of the duck as said stiffening material, said adhesive coating being anchored to the fibrous structure of the duck.

3. A reinforcing tape comprising a strip of woven fabric, a, coating of thermoplastic stiffening material on one side of said fabric extending into the substance thereof, stopping short of the. opposite side thereof and not affecting substantially the fibrous characteristics of the surface of the fabric, and a coating of pressure-sensitive adhesive of a rubber-like nature on the same side of the fabric as said thermoplastic stiffening material, said adhesive coating extending into the substance of said fabric but stopping short of the opposite side thereof.

4. A reinforcing material comprising woven fabric, a coating on one side of said fabric of thermoplastic coal tar pitch softening at a temperature of about to 0., said pitch ex tending into the substance of said fabric, 'stopping short of the opposite side thereof and not substantially affecting the fibrous characteristics of the surface of the fabric, and a coating of rubber on the same side of the fabric as said pitch, said rubber extending into the substance of said fabric but stopping short of theopposite side thereof and being anchored to the fibrous structure of said fabric. 5. Reinforcing material comprising woven fabric, a coating on one side of said fabric of Nuba, pitch, said Nuba pitch extending into the substance of said fabric, stopping short of the opposite side thereof and not substantially affecting the fibrous characteristics of the surface ofthe fabric, and a coating of pressure-sensitiveadhesive on the same side of the fabric as said Nuba pitch, said adhesive extending into the ubstance of said fabric but stopping'short of the opposite side thereof and being anchored to the fibrous structure of said fabric.

6. A reinforcing tape comprising a strip of duck, the transverse threads of which are sufflciently strong so that a one-inch length of strip STANLEY M. GRISWQLD. 

